Relationship Between Vaccines Against Coronavirus Disease 2019 (Covid-19) and Myocarditis

Relationship between vaccines against coronavirus disease 2019 (COVID-19) and myocarditis Lorena Araujo Silva Dias1, Nathalia Monerat Pinto Blazuti Barreto1 1Faculty of Medicine, Centro Universitario de Volta Redonda, Volta Redonda-Brazil. Background: Due to 2019 coronavirus disease (COVID-19) pandemic, it was necessary to develop a vaccine able to reduce the severity of the disease, decreasing hospitalization and death. The approval of the emergency use of these immunizers brought concerns about monitoring possible adverse effects, including myocarditis. Objective: To analyse the incidence of myocarditis after immunization against COVID-19. Method: Systematic review using the PRISMA method, searching the bibliographic databases PubMed, Cochrane and Scielo, April 2022, with the following descriptors: [covid-19 vaccine] AND [myocarditis] AND [adverse effect]. Inclusion criteria were articles published in the last 5 years approaching review, systematic review and meta-analysis type that addressed the association of immunization against COVID-19 with the development of myocarditis, in English. A total of 162 articles were found and 24 were eligible. Discussion: Vaccines can induce an immune response including antibodies production against pathogens. Due to COVID19, vaccines were developed with different technologies such as messenger RNA and, as their side effect, myocarditis has been observed, mostly in young adults and male teenagers, days after immunization and usually after the second dose. Studies suggest that a possible cause for the male incidence of post-vaccine myocarditis would be the difference in sexual hormones in the immune response. Conclusion: More research should be carried out to understand better the risk-benefit ratio of COVID-19 vaccines, even though there are already reports where the benefits and effectiveness of vaccines against COVID-19 have been shown outweighing the risk of myocarditis.